💡No Need to Set Primary Key in Core Data/SwiftData

TL;DR: Core Data and SwiftData auto-manage primary keys using SQLite’s Z_PK (auto-increment), Z_ENT (entity type), and Z_PRIMARYKEY (key tracking), eliminating the need for manual primary key setup.

Question:

For iOS developers, one common question when using Core Data or SwiftData is: why don’t these frameworks require setting a primary key, like other databases?

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Answer:

The answer lies in the underlying SQLite database where both frameworks automatically implement a robust primary key mechanism:

1. Auto-Incremented Primary Key (Z_PK): Each entity table…